Apparatus and method for ligament reconstruction

ABSTRACT

Apparatus for reconstructing a ligament, the apparatus comprising: a fixation device for maintaining a graft ligament in a bone hole, the fixation device comprising: a fixation screw comprising a body having screw threads formed thereon; and a ligament spacer mounted to the fixation screw, the ligament spacer comprising a canted face disposed opposite the fixation screw; such that when a graft ligament is disposed within a bone hole, the fixation screw and ligament spacer may be advanced into the bone hole alongside the graft ligament so that the fixation screw creates an interference fit between the graft ligament and the wall of the bone hole, and the ligament spacer creates an interference fit between the graft ligament and the wall of the bone hole, with the canted face of the ligament spacer being aligned with the adjacent surface of the bone.

REFERENCE TO PENDING PRIOR PATENT APPLICATIONS

This patent application claims benefit of:

(i) pending prior U.S. Provisional Patent Application Ser. No.61/498,663, filed Jun. 20, 2011 by Kelly G. Ammann for APPARATUS ANDMETHOD FOR ANATOMIC ACL RECONSTRUCTION (Attorney's Docket No. AMMANN-2PROV); and

(ii) pending prior U.S. Provisional Patent Application Ser. No.61/638,848, filed Apr. 26, 2012 by Kelly G. Ammann for APPARATUS ANDMETHOD FOR ANATOMIC ACL RECONSTRUCTION (Attorney's Docket No. AMMANN-3PROV).

The two (2) above-identified patent applications are hereby incorporatedherein by reference.

FIELD OF THE INVENTION

This invention relates to medical apparatus and methods in general, andmore particularly to medical apparatus and methods for reconstructing aligament.

BACKGROUND OF THE INVENTION

A ligament is a piece of soft, fibrous tissue that connects one bone toanother bone in the skeletal system. Ligaments can often become damagedor injured. When injured, ligaments may tear, rupture or become detachedfrom bone. The loss of a ligament can cause instability, pain andeventual increased wear on the joint surfaces, which can lead toosteoarthritis.

Various surgical techniques have been developed for ligament repair. Thesurgical technique that is used depends on the ligament that has beendamaged and the extent of the injury.

A ligament that is commonly injured is the anterior cruciate ligament(ACL). As seen in FIG. 1, the ACL 5 traverses from the top of the tibia10 to the bottom of the femur 15.

Trauma to the knee can cause injury to the anterior cruciate ligament(ACL). The ACL may become partially or completely torn. FIG. 2 depicts adiagram representation of a torn ACL 5 in the right knee.

A torn ACL reduces the stability of the knee joint and can result inpain, instability and additional wear on the cartilage surfaces of theknee, resulting in eventual osteoarthritis.

Several surgical techniques and ligament fixation devices are availablefor ACL repair. One of the most commonly used ACL repair techniquesinvolves removal of the native ACL ligament remnants, drilling tunnelsin both the femur and the tibia, inserting a tissue graft into thetunnels in place of the native ACL and securing the tissue graft inplace with interference screws or other fixation devices.

Looking now at FIG. 3, after removal of the injured native ACL,currently available aiming instruments are aligned to the tibia and aguide pin is drilled into the tibia. FIG. 3 illustrates a typical aimingdevice 20 for locating a guide pin (or guide wire) 25 from the outsideof the tibia 10 to an exit point inside the joint at the correspondinglocation of the tibial ACL insertion. Note that the guide pin 25 entersat an angle α to the tibia, and exits into the joint space at the angleα as measured from the upper surface of the tibia (also known as thetibial plateau).

The aiming device 20 is then removed from the tibia 10, leaving theguide wire 25 in place. A special cannulated drill 30 (i.e., a drillwith a center hole through the length of the drill) is slid over theguide wire 25 and drilled from the front surface of the tibia 10 intothe joint space of the knee. FIG. 4 shows the guide pin 25 and thecannulated drill 30 after drilling through the tibia.

A similar process is followed for drilling into the femur (FIG. 5). Theguide pin 25 is inserted through the tibial tunnel 35 into the femur 15near the femoral insertion site of the native ACL, and then the femoraltunnel 40 is drilled into femur 15, as shown in FIG. 5.

The method described above and shown in FIG. 5 is sometimes referred toas transtibial femoral tunnel drilling since the femoral tunnel 40 isdrilled by access through the tibial tunnel 35. One problem withtranstibial femoral tunnel drilling is that the femoral tunnel locationends up higher in the femoral notch than the normal anatomic femoralinsertion of the ACL because access to the femur is limited by the sizeand location of the tibial tunnel 35. An alternative method that hasbeen developed and is in current use is to create the femoral tunnel bydrilling through the anteromedial portal 45 (FIG. 6). Anteromedial (AM)portal drilling of the femoral tunnel 40 involves drilling across theknee joint through the AM portal skin incision 45 such that the femoraltunnel location can be brought into a more anatomic position. In AMportal drilling, a guide pin 25 is first drilled into the anatomiclocation on the femur through the AM portal 45, followed by drillingwith a cannulated drill 30 as shown in FIG. 6. The guide pin 25 and thecannulated drill 30 enter the AM portal 45 and traverse across the jointspace. As shown in FIG. 6, it is clear that the guide pin 25 and drill30 must pass in front of the adjacent femoral condyle to preventdamaging the condyle. The knee quite often must be put into a state ofdeep flexion in order to reach the anatomic ACL footprint on the femurand still safely pass by the adjacent condyle and the tibial plateau.

With the tibial tunnel 35 and the femoral tunnel 40 created, the tissuegraft 50 (FIG. 7A) is prepared. The tissue graft 50 is typicallyharvested from the patient's own body tissue and may be hamstringtendons, quadriceps tendon, or patellar tendon. Alternatively, similartissue grafts may be harvested from a donor and also include theAchilles tendon, anterior tibialis tendon or other graft sources. Thegraft 50 is first prepared by creating one long tissue graft strand,folding the graft over onto itself, and making measurements along thegraft. See FIG. 7A. Example measurements for adults are 30 mm of graftlength for the portion of the graft that is inserted into the femoraltunnel, 27 mm of graft length for the portion of the graft that isintra-articular (inside the knee joint) and 35 mm of graft length forthe portion of the graft that is inserted inside the tibial tunnel. Thetissue graft 50 is folded over into two bundles 60, 65 as shown in FIG.7A. Sutures are applied at the areas of the graft 50 that will interfacewith the tunnel fixation to add additional strength. The folded section55 will interface with the femoral tunnel 40 and the two opposite ends60, 65 will be in the tibial tunnel 35.

Additional sutures are looped around the folded portion 55 of the graft50, forming a strand of sutures 70 (or lead sutures) that can be used topull the graft 50 into place (FIG. 7B). The lead sutures 70 are passedthrough the tibial tunnel 35 and femoral tunnel 40, with the assistanceof a suture passing guide wire (not shown). FIG. 7B shows the foldedover graft in position to be pulled through the tibial tunnel 35 andinto the femoral tunnel 40. The lead sutures 70 (upper left in FIG. 7B)are grasped with a clamp 75 outside the femur and the graft construct ispulled through the tibial tunnel 35, through the interior of the kneejoint, and into the femoral tunnel 40.

Once the tissue graft 50 is in place, the individual bundles 60, 65making up the aggregate tissue graft may be manipulated to approximatetheir anatomic positions.

More particularly, advances in the research of ACL anatomy indicate thatthere are two primary bundles that make up the natural ACL, theanteromedial bundle 80 (FIG. 8) and the posterolateral bundle 85. Theanteromedial bundle 80 and the posterolateral bundle 85 are alsosometimes referred to as the AM bundle and the PL bundle. The name ofthe ligament refers to their point of origin on the tibial plateau, thatis, the AM bundle originates anteromedially and the PL bundle originatesposterolaterally (relative to each other on the tibial plateau). FIG. 8illustrates the two bundles and their relative positions in the kneejoint. Points A and B (FIG. 8) illustrate the ligament insertions on thetibial plateau as well as the ligament insertions on the femur. The AMand PL bundles cross each other during normal flexion of the knee joint.The AM and PL bundles are roughly parallel to each other when the kneeis in full extension.

In the typical surgical technique, the tissue graft 50 is manipulatedinto positions (FIG. 9) such that the two graft strands 60, 65 (makingup the aggregate tissue graft) approximate the locations of the AM andPL bundles and yield a reconstruction that approximates the native ACLanatomy. It has been demonstrated in biomechanical tests that thisconstruct results in a more stable result. There are several techniquesand devices which are used to approximate the footprint of the AM and PLbundles.

After the AM and PL bundles are manipulated into position, fixationscrews 90 (also known as interference screws) are inserted (e.g., intothe femoral tunnel 40 and then into the tibial tunnel 35). First thefemoral portion of the graft is fixed into place by inserting aninterference screw 90 through the AM portal 45 and into the femoraltunnel 40, as shown in FIG. 9. The interference screw 90 squeezes theligament graft tightly up against the tunnel wall so as to secure theligament graft in position within the tunnel. As the interference screw90 is tightened into place, it creates an interference fit between thetunnel, the graft and the screw.

FIG. 10 shows the femoral fixation in place, with the AM bundleapproximating its anatomic position and the PL bundle approximating itsanatomic position.

Lastly, an interference screw 90 (FIG. 11) is inserted into the tibialtunnel 35, thereby completing the fixation of the tissue graft. FIG. 11illustrates the final construct.

The foregoing technique has been used for many years for reconstructionof the ACL. This technique has been very successful, but it does havelimitations. More particularly, a closer look at the current techniquereveals limitations due to the geometry of the drilled holes and the useof currently available fixation devices.

More particularly, because the drill 30 enters the femoral notch at anangle, the entrance of the femoral tunnel 40 into the femur 15 iselliptical (FIG. 12). Note that this is not due to poorly manufactureddrills, or poor surgical technique, etc.—it is simply the normal resultof drilling a hole into a surface with the drill set at an angle to thesurface. This becomes more evident when viewing the tunnel straight into(i.e., perpendicular to) the bone surface, as shown in FIG. 12.

Similarly, because the drill 30 exits the tibial tunnel 35 and entersthe interior of the joint at an angle, the shape of the tibial tunnel 35is elliptical at the entrance to the joint space (FIG. 13). Thisphenomenon has been documented in various biomechanical studies.

Typical interference screws 90 fixate the graft ligament 50 along thelength of the screw and about the perimeter of the screw. However, theportion of the ligament disposed in the elliptical portion of a bonetunnel (i.e., that portion of the bone tunnel that does not form acomplete circular cross-section) is not secured against bone, as shownin FIG. 14.

The fixation screw 90 and the ligament graft 50 are represented in FIG.15. The AM and PL bundles are essentially free to reside wherever theymay land around the perimeter of the interference screw and are notsecured in the elliptical portion of the bone tunnel, because thatelliptical portion of the bone tunnel does not form a complete circularcross-section.

On the tibial side, a similar geometric condition exists (FIG. 16).Furthermore, the taper of the typical interference screw 90 at itsdistal end, which is disposed near the joint side mouth of the tibialtunnel 35, adds additional laxity to the ligament fixation, as shown inthe tibial cross-section of FIG. 16. This figure shows a standardinterference screw 90 secured in the tibial tunnel 35. The AM and PLbundles are shown roughly in their anatomic positions. The area at thedistal end of the interference screw 90 shows how the ligament 50 is notsecurely fixated in the area near the distal tip of the screw (i.e.,where the ligament enters the joint space). This type of limitedfixation may contribute to problems such as the so-called “windshieldwiper effect” (where the graft ligament sweeps across the mouth of thebone tunnel, thereby causing abrasion to the graft ligament and to themouth of the bone tunnel), and joint laxity (due to incomplete fixationof the ligament into its anatomic position).

As discussed above, there are potential problems with currentinterference screw fixation, i.e., there is a lack of complete fixationof the ligament graft at the entrance of the tunnel to the joint space.The unsecured ligament in the elliptical opening of the bone tunnel maycontribute to the windshield wiper effect, biomechanical instability andtunnel widening. Furthermore, the rotational position of the ligamentgraft in the tunnel is not controlled, which can result in abiomechanical construct that does not reproduce the native anatomy,i.e., the ligament strands 60, 65 may not be properly disposed in thelocations of the native AM and PM bundles.

Thus there is a need for new apparatus and method for reconstructing aligament which addresses deficiencies in the prior art.

SUMMARY OF THE INVENTION

The present invention provides new apparatus and method for fixation ofthe ACL which addresses deficiencies in the prior art. The new apparatussecures the graft ligament along the entire periphery of the ellipticalbone tunnel entrance so as to provide complete fixation of the ligamentgraft and to spread the ligament graft over the natural anatomicfootprint of the ACL insertions of both the tibia and femur. As anadditional benefit, the new apparatus substantially completely fills thebony defect resulting from the drilling process. The elliptical openingof the bone tunnel no longer becomes a detriment, but rather an asset,towards achieving a more accurate anatomic reconstruction.

In one preferred form of the invention, there is provided apparatus forreconstructing a ligament, the apparatus comprising:

a fixation device for maintaining a graft ligament in a bone hole, thefixation device comprising:

-   -   a fixation screw comprising a body having screw threads formed        thereon; and    -   a ligament spacer mounted to the fixation screw, the ligament        spacer comprising a canted face disposed opposite the fixation        screw;    -   such that when a graft ligament is disposed within a bone hole,        the fixation screw and ligament spacer may be advanced into the        bone hole alongside the graft ligament so that the fixation        screw creates an interference fit between the graft ligament and        the wall of the bone hole, and the ligament spacer creates an        interference fit between the graft ligament and the wall of the        bone hole, with the canted face of the ligament spacer being        aligned with the adjacent surface of the bone.

In another preferred form of the invention, there is provided anapparatus for reconstructing a ligament, the apparatus comprising:

a first fixation device for maintaining a graft ligament in a first bonehole, the first fixation device comprising:

-   -   a first fixation screw comprising a body having screw threads        formed thereon; and    -   a first ligament spacer mounted to the first fixation screw, the        first ligament spacer comprising a first canted face disposed        opposite the first fixation screw;    -   such that when a graft ligament is disposed within the first        bone hole, the first fixation screw and first ligament spacer        may be advanced into the first bone hole alongside the graft        ligament so that the first fixation screw creates an        interference fit between the graft ligament and the wall of the        first bone hole, and the first ligament spacer creates an        interference fit between the graft ligament and the wall of the        first bone hole, with the first canted face of the first        ligament spacer being aligned with the adjacent surface of the        first bone; and

a second fixation device for maintaining the graft ligament in a secondbone hole, the second fixation device comprising:

-   -   a second fixation screw comprising a body having screw threads        formed thereon; and    -   a second ligament spacer mounted to the second fixation screw,        the second ligament spacer comprising a second canted face        disposed opposite the second fixation screw;    -   such that when the graft ligament is disposed within the second        bone hole, the second fixation screw and second ligament spacer        may be advanced into the second bone hole alongside the graft        ligament so that the second fixation screw creates an        interference fit between the graft ligament and the wall of the        second bone hole, and the second ligament spacer creates an        interference fit between the graft ligament and the wall of the        second bone hole, with the second canted face of the second        ligament spacer being aligned with the adjacent surface of the        second bone.

In another preferred form of the invention, there is provided a methodfor reconstructing a ligament, the method comprising:

providing a fixation device for maintaining a graft ligament in a bonehole, the fixation device comprising:

-   -   a fixation screw comprising a body having screw threads formed        thereon; and    -   a ligament spacer mounted to the fixation screw, the ligament        spacer comprising a canted face disposed opposite the fixation        screw;    -   such that when a graft ligament is disposed within a bone hole,        the fixation screw and ligament spacer may be advanced into the        bone hole alongside the graft ligament so that the fixation        screw creates an interference fit between the graft ligament and        the wall of the bone hole, and the ligament spacer creates an        interference fit between the graft ligament and the wall of the        bone hole, with the canted face of the ligament spacer being        aligned with the adjacent surface of the bone;    -   forming a bone hole in a bone;    -   extending a graft ligament along the bone hole;    -   advancing the fixation screw and the ligament spacer into the        bone hole alongside the graft ligament so as to secure the graft        ligament in the bone hole.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention will bemore fully disclosed or rendered obvious by the following detaileddescription of the preferred embodiments of the invention, which is tobe considered together with the accompanying drawings wherein likenumbers refer to like parts, and further wherein:

FIG. 1 is a schematic view showing the femur, the tibia and the anteriorcruciate ligament of the left knee;

FIG. 2 is a schematic view showing a torn ACL in the right knee;

FIG. 3 is a schematic view showing an aiming device and a guide wire;

FIG. 4 is a schematic view showing a guide pin and a cannulated drillentering the joint space of the knee;

FIG. 5 is a schematic view showing a femoral tunnel, a guide pin and acannulated drill;

FIG. 6 is a schematic view showing drilling through the AM portal in theright knee;

FIG. 7A is a schematic view showing a prepared tissue graft;

FIG. 7B is a schematic view showing a tissue graft insertion into thetibial and the femoral tunnels;

FIG. 8 is a schematic view showing the AM and PL bundles of the ACL;

FIG. 9 is a schematic view showing the insertion of an interferencescrew into the femoral tunnel of the right knee;

FIG. 10 is a schematic view showing an interference screw in place inthe right knee;

FIG. 11 is a schematic view showing a completed ACL reconstruction inthe right knee;

FIG. 12 is a schematic view showing the resulting elliptical/oval tunnelentrance of the bone hole on the femur;

FIG. 13 is a schematic view showing the resulting elliptical/oval tunnelexit formed on the tibial plateau;

FIG. 14 is a schematic view showing the femur and a normal tunnelentrance and standard fixation;

FIG. 15 is a schematic view showing the femur and a standard fixationand ligament grafts;

FIG. 16 is a schematic view showing the interference screw and theligament graft disposed in the tibial tunnel;

FIG. 17A is a schematic view showing a guide pin through the AM portalwhich is centered on the femoral ACL footprint in the left knee;

FIG. 17B is a schematic view showing the placement of a guide pinthrough the AM portal;

FIG. 17C is a schematic view showing the knee in 90° flexion and showinginsertion of a guide pin through the AM portal at an angle 13;

FIG. 18 is a schematic view showing a cannulated drill disposed over theguide pin;

FIG. 19A is a schematic view showing the femoral tunnel drilled andhaving an elliptical entrance;

FIG. 19B is a schematic view showing the angle α₂ reduced from theoriginal angle α;

FIG. 19C is a schematic view showing the tibial tunnel “mouth”, orentrance, to the joint space;

FIG. 20 is a schematic view showing the femoral fixation screw (FFS);

FIG. 21 is a schematic view showing the femoral ligament spacer (FLS);

FIG. 22 is a schematic view showing the femoral fixation device;

FIG. 23 is a schematic view showing a cross-section of the femoralfixation device;

FIG. 24 is a schematic view showing the femoral fixation device;

FIG. 25 is a schematic view showing the femoral fixation device;

FIG. 26A is a schematic view showing the femoral fixation device;

FIG. 26B is a schematic view showing the femoral fixation device andshowing the angle 13;

FIG. 27 is a schematic view showing the lead-in and canted face of thefemoral fixation device;

FIG. 28 is a schematic view showing insertion of the femoral fixationdevice;

FIG. 29 is a schematic view showing the femoral fixation device andligament graft in position;

FIG. 30 is a schematic view showing the femoral fixation device andligament bundles;

FIG. 31A is a schematic view showing the femoral fixation deviceinserted, but with the graft ligament not shown, to illustrate thecongruence of fixation to the femoral surface;

FIG. 31B is a view similar to that of FIG. 31A, but taken from adifferent angle of view;

FIG. 32 is a schematic view showing the femur and tibia, femoralfixation and the graft bundles;

FIG. 33 is a schematic view showing the tibial ligament spacer and guidepin, but without ligament grafts in order to facilitate viewing;

FIG. 34 is a schematic view showing the tibial ligament spacer (TLS);

FIG. 35 is a schematic view showing the tibial fixation screw (TFS);

FIG. 36 is a schematic view showing the tibial fixation screw and tibialligament spacer, in unassembled condition;

FIG. 37A is a schematic view showing the tibial fixation device;

FIG. 37B is a schematic view showing the tibial fixation device and theangle α;

FIG. 38 is a schematic view showing the tibial fixation device;

FIG. 39 is a schematic view showing the tibial fixation device;

FIG. 40 is a schematic view showing the impactor introduced and alignedwith the TLS;

FIG. 41 is a schematic view showing the TLS seated into tibia, and theAM and PL bundles;

FIG. 42 is a schematic view showing the guide wire inserted into thetibia;

FIG. 43 is a schematic view showing the TFS advancing over the guidewire to engage with the TLS;

FIG. 44 is a schematic view showing the tibial fixation screw partiallyinserted;

FIG. 45 is a schematic view showing the tibial fixation device andligaments;

FIG. 46 is a schematic view showing completed anatomic ACLreconstruction;

FIG. 47 is a schematic view showing holes or fenestrations through theFLS;

FIG. 48 is a schematic view showing fenestrations through the TLS;

FIG. 49 is a schematic view showing a fenestrated femoral ligamentspacer;

FIG. 50 is a schematic view showing a fenestrated tibial ligamentspacer;

FIG. 51 is a schematic view showing an FLS with retaining barbs;

FIG. 52 is a schematic view showing a TLS with retaining barbs;

FIG. 53 is a schematic view showing a femoral fixation device withfenestrations, recesses and barbs;

FIG. 54 is a schematic view showing a tibial fixation device, withfenestrations, recesses and barbs;

FIG. 55 is a schematic view showing femoral and tibial fixation device(with fenestrations) in place;

FIG. 56 is a schematic view showing femoral and tibial fixation devicesin the final construct;

FIG. 57 is a schematic view showing femoral and tibial fixation devicesand ligament grafts;

FIG. 58 is a schematic view showing a fixation where a first tunnel isdrilled slightly smaller, e.g., 9 mm;

FIG. 59 is a schematic view showing a counterbore being drilled somewhatlarger, e.g., 11 mm;

FIG. 60 is a schematic view showing a stepped drill bit;

FIG. 61 is a schematic view showing the bore/counterbore hole beingdrilled with the stepped drill bit;

FIG. 62 is a schematic view showing an alternative femoral fixationdevice with larger FLS;

FIG. 63 is a schematic view showing an expanded femoral fixation devicewith a larger FLS;

FIG. 64 is a schematic view showing a femoral fixation device;

FIG. 65 is a schematic view showing an expanded femoral fixation (largerFLS) insertion;

FIG. 66 is a schematic view showing an expanded femoral fixation;

FIG. 67 is a schematic view showing a femoral guide wire aimer;

FIG. 68 is a schematic view showing a femoral guide wire aimer and guidewire;

FIG. 69 is a schematic view showing a tunnel entrance with guide wire;

FIG. 70 is a schematic view showing an elliptical tibial aimer forassessing footprint and aiming the guide wire;

FIG. 71 is a schematic view showing a plug with a canted tip to achievean anatomic footprint and “splay” the ligament grafts;

FIG. 72 is a schematic view showing an example of an alternativelyshaped FLS (or TLS);

FIG. 73 is a schematic view showing a femoral fixation device;

FIG. 74 is a schematic view showing a femoral fixation screw;

FIG. 75 is a schematic view showing a femoral ligament spacer;

FIG. 76 is a schematic view showing a femoral fixation screw alignedwith a femoral ligament spacer;

FIG. 77 is a schematic view showing an assembled femoral fixationdevice;

FIG. 78 is a schematic view showing a femoral fixation device;

FIG. 79A is a schematic view showing a femoral fixation device;

FIG. 79B is a schematic view showing femoral fixation with tissue graft;

FIG. 80 is a schematic view showing a femoral fixation device;

FIG. 81 is a schematic view showing a femoral fixation device;

FIG. 82 is a schematic view showing a femoral fixation device;

FIG. 83 is a schematic view showing a femoral fixation device;

FIG. 84A is a schematic view showing a guide pin and a femoral fixationdevice;

FIG. 84B is a schematic view showing a femoral fixation device, a guidepin and ligament grafts;

FIG. 85 is a schematic view showing a ligament spacer alignment tool;

FIG. 86 is a schematic view showing a hex wrench and ligament spaceralignment tool;

FIG. 87 is a schematic view showing a hex wrench extending through aligament spacer alignment tool;

FIG. 88A is a schematic view showing a ligament spacer alignment toolover a guide pin;

FIG. 88B is a schematic view showing a ligament spacer alignment tool,femoral fixation device and ligament grafts;

FIG. 89A is a schematic view showing a hex wrench about to engage afemoral fixation screw;

FIG. 89B is a schematic view like that of FIG. 89A, except also showinga tissue graft;

FIG. 90 is a schematic view showing a femoral fixation device;

FIG. 91A is a schematic view showing tools engaged with a femoralfixation device;

FIG. 91B is a schematic view showing tools engaged with a femoralfixation device, and showing ligament grafts;

FIG. 92 is a schematic view showing insertion of the femoral fixationdevice;

FIG. 93A is a schematic view showing a femoral fixation device seated inthe femur;

FIG. 93B is a schematic view showing a femoral fixation device seated inthe femur, with ligament grafts being shown;

FIG. 94A is a schematic view showing a final femoral construct;

FIG. 94B is a schematic view showing a final femoral construct, withligament graft;

FIG. 95A is a schematic view showing a final femoral construct;

FIG. 95B is a schematic view showing a final femoral construct, withligament graft;

FIG. 96 is a schematic view showing a tibial ligament spacer;

FIG. 97 is a schematic view showing a tibial ligament spacer;

FIG. 98 is a schematic view showing a tibial fixation screw;

FIG. 99 is a schematic view showing a tibial fixation screw;

FIG. 100 is a schematic view showing a tibial ligament spacer alignedwith a tibial fixation screw;

FIG. 101A is a schematic view showing a tibial ligament spacer assembledto a tibial fixation screw;

FIG. 101B is a schematic view showing a tibial ligament spacer withangled lead-in;

FIG. 102A is a schematic view showing a tibial fixation device;

FIG. 102B is a schematic view showing a tibial fixation device and aligament graft;

FIG. 103 is a schematic view showing a tibial fixation device disposedover a tibial alignment pin;

FIG. 104 is a schematic view showing a tibial fixation device, a guidepin, and hex wrench;

FIG. 105 is a schematic view showing a guide pin;

FIG. 106 is a schematic view showing a tibial alignment pin;

FIG. 107 is a schematic view showing a guide pin;

FIG. 108 is a schematic view showing a guide pin;

FIG. 109A is a schematic view showing a ligament tensioning bar disposedover a guide pin;

FIG. 109B is a schematic view showing a ligament tensioning bar disposedover the tibial alignment pin, and showing ligament graft sutures;

FIG. 110 is a schematic view showing a tibial fixation device, a wrench,and a tensioning bar disposed over a guide pin;

FIG. 111A is a schematic view showing a tibial fixation device and a hexwrench disposed over a guide pin;

FIG. 111B is a schematic view showing a tibial fixation device and awrench disposed over a guide pin, and showing ligament graft;

FIG. 112 is a schematic view showing a wrench engaged with a tibialfixation screw;

FIG. 113A is a schematic view showing the overall tibial system;

FIG. 113B is a schematic view showing the overall tibial system, withligament graft and sutures;

FIG. 114 is a schematic view showing the overall tibial system;

FIG. 115 is a schematic view showing a wrench tightening the tibialfixation device into position;

FIG. 116 is a schematic view showing a tibial fixation device inposition;

FIG. 117 is a schematic view showing instrumentation disengaged from thetibial fixation device;

FIG. 118 is a schematic view showing tibial and femoral fixation devicesin place;

FIG. 119A is a schematic view showing tibial and femoral fixationdevices in place;

FIG. 119B is a schematic view showing tibial and femoral fixationdevices in place, with graft ligaments;

FIG. 119C is a schematic view showing tibial and femoral fixationdevices in position;

FIG. 119D is a schematic view showing tibial and femoral fixationdevices in position, with graft ligament;

FIG. 120A is a schematic view showing tibial and femoral fixationdevices in position;

FIG. 120B is a schematic view showing tibial and femoral fixationdevices in position, with graft ligament;

FIG. 121A is a schematic view showing a spacer orientation guide;

FIG. 121B is a schematic view showing insertion of a spacer orientationguide into the femoral tunnel;

FIG. 122 is a schematic view showing a spacer orientation guide fullyinserted into the femoral tunnel and aligned with the bone surface;

FIG. 123 is a schematic view showing a bone marked in the same locationas the guide alignment mark;

FIG. 124A is a schematic view showing a spacer alignment tool withalignment marking;

FIG. 124B is a schematic view showing a femoral ligament spacer havingan alignment marking;

FIG. 125 is a schematic view showing an FLS tightened, with its markingaligned with a marking on the bone;

FIG. 126 is a schematic view showing an FLS in place and aligned with abone mark;

FIG. 127 is a schematic view showing a spacer orientation guide alignedwith a tibial surface;

FIG. 128 is a schematic view showing an alignment marking on a tibia;

FIG. 129 is a schematic view showing an alignment marking on a tibialligament spacer; and

FIG. 130 is a schematic view showing a TLS inserted and aligned with amarking on the tibial surface.

DETAILED DESCRIPTION OF THE INVENTION

As noted above, the present invention provides new apparatus and methodfor fixation of the ACL which addresses deficiencies in the prior art.The new apparatus secures the graft ligament along the entire peripheryof the elliptical bone tunnel entrance so as to provide completefixation of the ligament graft and to spread the ligament graft over thenatural anatomic footprint of the ACL insertions of both the tibia andfemur. As an additional benefit, the new apparatus substantiallycompletely fills the bony defect resulting from the drilling process.The elliptical opening of the bone tunnel no longer becomes a detriment,but rather an asset, towards achieving a more accurate anatomicreconstruction.

First Preferred Construction and Method of Use

In accordance with the present invention, and looking now at FIGS. 17Aand 17B (which show the left knee), the femoral tunnel is prepared byfirst placing a guide pin 25 into the anatomic location of the femoralACL insertion. It is desirable for the guide pin 25 to enter theintercondylar notch at an angle to avoid the adjacent medial condyle aswell as the tibial plateau. As noted above, this angle of approachresults in the formation of the aforementioned elliptical femoral tunnelentrance.

From a top view (FIG. 17C), with the knee in 90° flexion, the path ofthe guide pin 25 is shown as it passes the medial condyle and enters themedial aspect of the intercondylar notch. The guide pin 25 enters at anangle β from the sagittal plane. The angle β is significant, in order toclear the adjacent medial condyle and to create the elliptical tunnelentrance.

Placement of the guide pin 25 in this manner allows access to theanatomic femoral insertion of the ACL. The drill 30 is then slid overthe guide pin 25 (FIG. 18), through the anteromedial portal 45, past themedial condyle and tibial plateau, and into the anatomic location of thefemoral ACL insertion.

The femoral tunnel 40 (FIG. 19A) is then drilled, and the result is acircular bore hole with an elliptical tunnel entrance. This portion ofthe technique is similar to that which was presented earlier, exceptthat it is completed with the understanding that the angled entrance tothe femoral tunnel contributes in a positive manner to creating a moreanatomic tunnel entrance. As such, the surgeon does not try to“straighten” out the tunnel to achieve a circular entrance, but rathermay slightly increase the angle 13 to achieve the more anatomicelliptical entrance. This is a significant advantage over the prior art.

Similarly, the tibial tunnel (FIG. 19B) is prepared by first drilling aguide pin 25 (with the aid of a drill guide 20) through the anteromedialsurface of the tibia 10, exiting through the anatomic center of the ACLinsertion on the tibial plateau (as previously described). The angle α₂of the tibial tunnel can be smaller than the original angle α in atypical reconstruction, because the elliptical/oval nature of the tibialtunnel exit into the joint space contributes to the anatomicreconstruction due to the novel aspects of the present invention. Thiscan be a significant advantage over the prior art, since a shortertunnel means less trauma to the tibia and more space on the bone surfacebelow the tibial tunnel for other surgical procedures, if needed. Thedrill guide 20 is removed, and the cannulated drill is placed over theguide pin 25. The cannulated drill is then drilled from the outside ofthe tibia through to the tibial plateau, exiting the tibia at theanatomic footprint of the ACL insertion. FIG. 19C illustrates the effectof the angle α₂ on the tunnel entrance into the joint space (i.e., FIG.19C shows a circular section 95 for reference, a conventional ellipse100 formed by a bone tunnel drilled at angle α, and the elongatedellipse 105 formed by a bone tunnel drilled at angle α₂ in accordancewith the present invention). As seen in FIG. 19C, the tibial tunnelentrance into the joint space becomes a more elongated ellipse,increasing the footprint of the ACL graft insertion and contributing toa more anatomic reconstruction.

The prepared graft ligament 50 is then inserted through the tibialtunnel and into the femoral tunnel. This is done in a manner similar tothe method described earlier, i.e., the graft ligament 50 is folded overat 55 such that there are two graft bundles 60, 65 that make up theaggregate ligament graft (FIG. 7A). Sutures are looped around the graftat the area 55 where the graft is folded over. A guide pin (not shown),with an eyelet for passing the sutures, is inserted through the tibialtunnel 35, through the joint space and through the femoral tunnel 40.The guide pin exits through the skin opposite the femoral tunnel. Thesutures are then grasped (e.g., with a clamp) and the graft is pulledthrough the tibial tunnel, through the joint space and into the femoraltunnel. The AM and PL graft bundles (i.e., the graft bundles 60, 65) aremanipulated into their approximate anatomic locations.

Next, and looking at FIGS. 20-23, a new femoral fixation device 110,comprising a femoral fixation screw (FFS) 115 and a femoral ligamentspacer (FLS) 120, is introduced into the femoral tunnel 40 so as tofixate the graft ligament into place within the femoral tunnel.

More particularly, femoral fixation screw (FFS) 115 comprises a screwbody 125 with a necked down region 130 and a head 135. The body 125 offemoral fixation screw (FFS) 115 provides aperture ligament fixation asit is screwed into the femoral tunnel. The fixation screw 115 tapers orcurves to a narrow distal end to allow easy starting and insertion intothe femoral tunnel. Also, the femoral fixation screw 115 is cannulatedat 140 to allow the use of a guide pin to guide the femoral fixationscrew straight into the femoral tunnel. A hex socket 145 (or hexalobesocket, square socket or other shaped socket) resides at the near end ofthe femoral fixation screw to engage with an insertion (tightening)tool.

The femoral ligament spacer (FLS) 120 comprises a substantially tubularbody 150 which is cut off at an angle to form an elliptical face 155.The tubular body 150 has in internal diameter 160 that is opened up at165 to receive and capture the screw head 135 of FFS 115, as willhereinafter be discussed. The femoral ligament spacer 120 spreads the AMand PL bundles as the femoral fixation screw 115 is tightened intoplace. The femoral ligament spacer 120 can rotate freely on the femoralfixation screw 115, thus allowing the desired alignment of theligaments. Furthermore, the angled surface 155 of the femoral ligamentspacer 120 aligns to the bony surface of the femur such that the bonydefect (i.e., the elliptical entrance to the femoral tunnel) iscompletely filled, and the ligament graft fully supported, about theentire elliptical mouth of the bone tunnel. The angled surface 155 ofthe FLS 120 may be formed or manufactured in a variety of angles orshapes to best match the mouth of the femoral tunnel. The angled surface155 corresponds to the angle β (FIG. 17C) and closely approximates thecontour of the mouth of the femoral tunnel.

As seen in FIG. 23, the femoral ligament spacer 120 is captured onto thefemoral fixation screw 115 by means of a reversed external thread formedon the head 135 of the screw 115 and a reversed internal thread 170formed on the distal end of femoral ligament spacer 120. To assemble FLS120 on FFS 115, the FLS 120 is aligned with the FFS 115 as shown in FIG.22, and the two parts are screwed together as shown in FIG. 23 untilhead 135 of FFS 115 is rotatably received in the enlarged diameter 165of FLS 120. In essence, the “necked down” region of FLS 120 whichresides distal to enlarged diameter 165 of FLS 120, and which carriesinternal thread 170 thereon, rotatably captures the FLS 120 to FFS 115.

Once assembled in this manner, the femoral ligament spacer 120 rotatesfreely around the groove 130 in the femoral fixation screw 115. Thecross-sectional view in FIG. 23 illustrates how the FLS 120 is rotatablyretained onto the FFS 115. It should be appreciated that this method ofattachment is meant merely as an example of a preferred construction;other means may be used for rotatably capturing the FLS 120 onto the FFS115, such as a separate screw fastener to hold the FLS to the FFS, or apressed-in stake with a head to capture the FLS to the FFS, etc. Notethat the femoral ligament spacer 120 provides access to the drivechannel of the femoral fixation screw 115 via the axial opening 160extending through the femoral ligament spacer (FIG. 23). The reversethreads 170 inside the FLS 120 are completely disengaged from thethreads on the head 135 of the FFS 115 after assembly. This allows theFLS 120 to rotate freely about the head 135 of the FFS 115.

The femoral ligament spacer 120 functions as a means to align graftligament strands into the mouth of the femoral tunnel and to completelyfill the bony defect at the mouth of the femoral tunnel. The femoralligament spacer 120 can be positioned so as to spread the ligaments intotheir anatomic position, regardless of the rotational position of thefemoral fixation screw 115 within the femoral tunnel. Thus, theconstruction of femoral fixation device 110 allows the rotationalposition of femoral ligament spacer 120 to be optimized for ligamentposition and ligament support, since it is independent of the rotationalposition of femoral fixation screw 115. Furthermore, femoral fixationdevice 110 may function as a “strain relief”, allowing the tension inthe ligament graft to spread over the length of the femoral fixationdevice. The components of the femoral fixation device 110 may be madefrom metal, plastic or bioabsorbable material. The femoral fixationdevice is inserted into the femoral tunnel as an assembled unit. SeeFIG. 24.

The end view shown in FIG. 25 illustrates the contours on the sides ofthe FLS 120 for ligament alignment. The outer wall 175 of FLS 120 isshaped with ligament recesses 180 to further engage with, and providealignment of, the graft ligament strands 60, 65. The shape of theligament spacer recesses 180 may comprise a variety of shapes to allowspace for the ligament graft strands 60, 65.

The particular ligament recesses 180 shown are provided for example onlyand may consist of other shapes such as flats, concave surfaces,corrugated surfaces, etc. The hole 160 through the center of the FLS 120is for the insertion tool to pass through the FLS 120 and access FFS115, thereby allowing the entire assembly to be tightened into place.The FLS 120 has smooth radii around critical corners to ensure strainrelieved fixation of the ligament graft bundles.

The FLS 120 is sized relative to the diameter of the FFS 115. The largerouter portion of the FLS 120 may be larger than the diameter of FFS 115to create an interference fit with the bone tunnel and to further spreadthe ligament graft strands apart and to secure the FLS 120 into thebone. This larger FLS diameter, nestled between the graft recesses, hasa self-aligning capability. As the femoral fixation device 110 istightened into place, the larger outer portions of FLS 120 glide on thebone surface, centering the spacer onto the elliptical entrance of thefemoral bone tunnel, and thus separating the ligament strands 60, 65into their AM and PL anatomic location.

The end 155 of the FLS 120 is angled (approximately equal to β) tocreate the mating elliptical, oval shape to fill the elliptical,oval-shaped entrance of the femoral tunnel. The angled shape of thefemoral ligament spacer 120 fills the bone tunnel entrance and urges theligament graft up against the tunnel entrance to mimic the wideranatomic footprint of the natural femoral insertion. The interferenceportion of the femoral ligament spacer 120 (i.e., the tips of FLS 120that engage tightly with the bone) guides the femoral ligament spacerinto the proper orientation on the bone. A side view of the femoralfixation device 110 is shown in FIG. 26A. The aforementioned angle β isillustrated in FIG. 26B.

In the bottom view of femoral ligament spacer 120 (FIG. 27), the FLS 120is shown with a lead-in surface 185 that helps start the FLS into thefemoral tunnel. The canted surface 155 is shown on the right portion ofthe image.

It will be appreciated that rotation of the femoral fixation screw 115seats the femoral ligament spacer 120 into the bone, thus securing theligaments into their anatomic position (i.e., via an interference fiteffected by femoral fixation screw 115 along the more distal portion ofthe femoral fixation device 110 and via an interference fit effected bythe femoral ligament spacer 120 along the more proximal portion of thefemoral fixation device 110).

Returning now to the preferred method of use, and looking now at FIG.28, the guide pin 25 is pulled back or re-inserted through the ligamentgraft. The femoral fixation device 110 (i.e., FFS 115 and FLS 120, withFLS 120 being rotatably captured on FFS 115) are inserted over the guidepin. The femoral fixation device 110 is screwed into the femoral tunnelwith the hex tool 190 (which passes through FLS 120 to engage the hexdrive 145 on FFS 115) and with the ligament grafts 60, 65 positionedinto their approximate anatomic locations. The femoral fixation device110 is preferably introduced into the femoral tunnel with the use of theguide pin 25, as shown in FIG. 28.

The AM bundle 60 and PL bundle 65 separate from each other onto theopposite sides of the FLS 120 as the FLS begins to engage with the mouthof the bone tunnel. The AM bundle 60 and PL bundle 65 may be manipulatedto spread out, with one bundle on each side of the FLS. The ligamentgraft bundles 60, 65 then align with, and fit in between, the recesses180 on the FLS and the periphery of the bone tunnel. As the femoralligament spacer 120 begins to engage with the bone surface, the surfaceof the FLS adjusts its rotational position (or may be manipulated intothe desired rotational position) urging the ligament graft strands 60,65 into their respective AM and PL bundle locations. See FIGS. 29 and30.

The femoral fixation device 110 provides at least the following usefulfunctions in ligament fixation:

(1) The final reconstructed ligament more closely imitates the naturalanatomic footprint of the femoral ACL insertion, resulting in abiomechanically superior reconstruction. The AM and PL bundles arespread out over the elliptical anatomic footprint at the mouth of thefemoral tunnel, with the femoral ligament spacer 120 holding the graftligament to the rim of the bone tunnel about the periphery of theelliptical mouth of the bone tunnel.

(2) The ligament is secured through the entire periphery of the bonetunnel, eliminating the possible “windshield wiper” action of the graftligament over the bone surface. This “windshield wiper” action can leadto wear of the ligament, wear of the bone surface, widening of the bonetunnel, and potentially a failed reconstruction.

(3) In the event that the graft ligament needs to be revised at a laterdate, the entire construct can be easily removed, simply by looseningthe interference screw (i.e., the femoral fixation screw 115) from thefemur. The femoral ligament spacer 120 and the femoral fixation screw115 (i.e., the interference screw) will remove as a single assembly,aiding in the revision process. Again, the opening in the FLS 120 allowsaccess to the drive socket 145 in FFS 115 so as to allow removal of FFS115 (and hence the complete femoral fixation device 110) from the femur.

(4) The femoral ligament spacer 120 also provides strain relief. Thestrain on the ligament graft is spread over the length of the femoralligament spacer, rather than the abrupt strain resulting from thetransition of a highly compressed ligament graft emerging from astandard interference screw/bone interface.

(5) Inasmuch as the present invention makes the formation of anelliptical femoral bone tunnel opening an asset rather than a liability,the motivation for drilling the femoral tunnel with the knee in deepflexion is significantly reduced, which can reduce trauma to thepatient's knee during the surgical procedure.

See also FIGS. 31A, 31B and 32.

A similar ligament spacer is utilized for tibial fixation. However, inthis version of the invention, and looking now at FIGS. 33-37A, thetibial ligament spacer (TLS) 195 is introduced first, and independentlyfrom, the tibial fixation screw (TFS) 200. The TLS 195 and the TFS 200together form the complete tibial fixation device 201. The TLS 195 isintroduced through the accessory anteromedial portal 45. It may beintroduced with a clamp or a special tool (not shown) that clips overthe TLS. See FIG. 33.

The TLS 195 is shown in detail in FIG. 34. There are similar features onthe TLS 195 as on the FLS 120. The features include the canted surface205 to form the elliptical shape, the lead-in 210 to aid insertion intothe bone tunnel, the recessed surfaces 215 for fixating the ligament inthe bone tunnel, and the cannulation 220 through the center of the TLS195 to receive a guide wire 25. The primary difference between thetibial ligament spacer 195 and the aforementioned femoral ligamentspacer 120 is that the tibial ligament spacer 195 has an extension 225from the body of the spacer that is threaded (FIG. 34). This threadedextension 225 engages with the tibial fixation screw 200 (e.g., as shownin FIG. 37A) during the installation of the tibial fixation screw sothat TLS 195 is connected to TFS 200, as will hereinafter be discussed.The threaded extension 225 of TLS 195 is initially used during theinstallation of the TLS in order to secure the TLS into place. Thethreaded extension 225 is also cannulated, allowing a guide pin 25 topass through its center. The threaded extension 225 has a thread pitchthat is specifically formed to reduce, or compress, the construct (i.e.,the complete tibial fixation device 201, consisting of the united TLS195 and TFS 200) during final installation (discussed below). The angledface 205 on TLS 195 may be formed, or manufactured, in a variety ofangles to match various tibial surfaces.

The tibial fixation screw (TFS) 200 is shown in FIGS. 35, 36 and 37A.The tibial fixation screw 200 consists of a body of threads for fixatingthe ligament graft against the bone tunnel wall via an interference fit.The distal end of tibial fixation screw 200 has a counterbore 230 thatis threaded to engage with the threaded extension 225 of the TLS 195(see FIGS. 36 and 37A). Alternatively, the TFS 200 may be made ofplastic and the counterbore 230 may be self-tapping orself-thread-forming as it engages with the TLS 195. The tibial fixationscrew 200 is cannulated throughout its length. The tibial fixation screw200 is preferably tapered toward its distal end to help with startingthe tibial fixation screw 200 into the tibial bone tunnel.

FIG. 36 illustrates the TFS 200 and the TLS 195 in unassembled form. Theexternal threads on the TLS 195 may have a pitch equal to the tibialfixation screw threads, or slightly less. A slightly smaller pitch willresult in additional reduction (compression) during final tightening ofthe TFS 200 to the TLS 195. In other words, as the tibial fixation screw(TFS) 200 is tightened to the tibial ligament spacer (TLS) 195, theexternal threads on the TLS extension 225 may advance slightly fasterinto the TFS 200 than the TFS 200 advances into the bone tunnel, thuscompressing the TFS and the TLS together as the TFS is tightened intothe bone tunnel.

In the final assembly of the TLS and the TFS (FIG. 37A), the tibialfixation screw 200 tightens up against, or very near to, the proximalsurface of the TLS 195.

FIG. 37 b illustrates the correspondence of angle α from the tunneldrilling technique to the canted surface 205 of the tibial ligamentspacer 195. The angled surface 205 at angle α creates a close anatomicalignment between the bone surface and the tibial fixation device 201,and also secures the ligament grafts into their anatomic positions.

Similar to the femoral fixation device 110, the tibial fixation device201 has graft recesses 215 on the top and bottom side of the tibialligament spacer 195 to urge the ligaments into their anatomic positions.See FIG. 38. The recesses 215 shown are again crescent-shaped (like therecesses for the femoral ligament spacer), but could be in some otherform if desired.

The TLS 195 is sized relative to the tibial fixation screw 200. In thisdesign, the graft recesses 215 are smaller in size than the diameter oftibial fixation screw 200 (FIG. 38). The interference portions 235 ofTLS 195 are larger than the screw diameter for alignment and ligamentseparation.

The tibial ligament spacer 195 functions as a means to align theligament strands 60, 65 into the bone tunnel and to fill the bony defectat the mouth of the bone tunnel. The tibial ligament spacer 195 can bepositioned to spread the ligament strands 60, 65 into their anatomicposition, regardless of the rotational position of the tibial fixationscrew 200. The components of tibial fixation device 201 may be made frommetal, plastic or bioabsorbable material. The tibial fixation device 201is advanced into the tibia as separate pieces, with the TLS 195 beingadvanced from the joint side (e.g., through AM portal 45) and the TFS200 being advanced from the exterior tibial surface (i.e., through thetibial tunnel), and thereafter joined together in situ (see below). FIG.39 shows the assembled tibial fixation device 201 in an isometric view.

Returning now to the discussion of the surgical technique for effectingtibial fixation of the graft ligament using tibial fixation device 201,a long cannulated positioning device 240 is introduced through thetibial tunnel (FIG. 40), between the strands of the ligament graft. Thepositioning device 240 is tightened onto the threaded portion of thetibial ligament spacer (TLS) 195. The positioning device 240 has aslidable impactor, or slap hammer 245, at the proximal end of thepositioning device. The positioning device 240 is used to orient the TLS195 to fill the mouth of the elliptical bone tunnel. The slidableimpactor 245 is then used to seat the TLS 195 into the tibial tunnel,with the ligaments spread appropriately (AM bundle on the anteromedialside and PL bundle on the posterolateral side) of the bone tunnel. Aunique aspect of the TLS 195 is that it provides ligament tensioningduring its insertion. See FIG. 41.

Next, a guide pin 25 is inserted through the cannulated positioningdevice 240 and through the TLS 195, as shown in FIG. 42.

The cannulated positioning device 240 is then removed, leaving the guidewire 25, the TLS 195 and the partially fixated ligaments (not shown) inthe tibial tunnel. The tibial fixation screw 200 is then inserted overthe guide wire 25. See FIG. 43.

With tension applied to the ligament strands (FIG. 44), the tibialfixation screw 200 is advanced into place (including into engagementwith the tibial ligament spacer 195) with a cannulated hex (or othersocket configuration) wrench. TFS 200 compresses the ligament strands60, 65 against the wall of the bone tunnel as it advances up the bonetunnel, thereby effecting an interference fixation of the graft ligamentwith the tibia. See FIG. 44, which shows the ligament strands withexternal tension, the partially inserted tibial fixation screw 200, theguide pin 25 and the tibial ligament spacer 195.

The tibial fixation screw 200 may be tightened until it is flush withthe tibia (i.e., with the proximal entrance of the bone tunnel) or untilit bottoms out onto the TLS 195. As described earlier, the threadpitches may be designed specifically to compress or reduce the constructas the tibial fixation screw 200 is tightened into place. After thetibial fixation screw 200 has engaged with the tibial ligament spacer195, the tibial fixation screw 200 is completely tightened into placeagainst the tibial ligament spacer 195. The guide wire 25 is thenremoved and the external ligament strands 60, 65 are trimmed up to theexternal surface of the tibia 10. FIG. 45 is a cross-sectional viewshowing engagement of the TLS 195 with the TFS 200.

See FIG. 46 for the completed reconstructed anatomic ACL using thefemoral fixation device 110 and tibial fixation device 201. With thisreconstruction, the AM and PL bundles 60, 65 are tensioned and fixatedinto their anatomic positions on both the femur and the tibia.

The tibial fixation device 201 provides at least the following usefulfunctions in ligament fixation:

(1) The final reconstructed ligament more closely imitates the naturalanatomic footprint of the tibial ligament insertion, resulting in abiomechanically improved reconstruction. The AM and PL bundles arespread out over the elliptical anatomic footprint at the joint-sidemouth of the tibial tunnel.

(2) The ligament is secured over the entire perimeter of the tibialtunnel, eliminating the “windshield wiper” action of the graft ligamentover the tunnel entrance at the bone surface. This “windshield wiper”action can lead to wear of the ligament, wear of the bone surface,widening of the bone tunnel, and potentially a failed reconstruction.

(3) The bony defect from the drilling process is substantiallycompletely filled by the tibial fixation device.

(4) The action of inserting the TLS 195 into the tunnel providestensioning of the ligament graft for easy insertion, ensuring tension tothe graft bundles.

(5) The action of rotating the interference screw (i.e., TFS 200) intoplace further fixates the ligament graft bundles, and may be used todraw the TLS 195 slightly deeper into the tibial bone tunnel foradditional security of the fixation.

(6) In the event that the ligament needs to be revised at a later date,the tibial fixation screw 200 is removed by unscrewing the interferencescrew from the tibia. The tibial ligament spacer 195 is then graspedagain with the positioning device 240 and then pulled completely throughthe tibial tunnel for removal.

(7) The tibial ligament spacer 195 provides a strain relief todistribute the stress over the face of the device to create a smooth andgradual transition from the compression of the tibial fixation screw200.

Alternatives for the First Preferred Construction and Method of Use

Alternative designs are envisioned for the femoral ligament spacer (FLS)120 and/or the tibial ligament spacer (TLS) 195.

The femoral ligament spacer (FLS) 120 and/or the tibial ligament spacer(TLS) 195 have been described above as a solid shape with a hole throughthe center. However, it may be desirable to have a porous version of theFLS 120 and/or the TLS 195. Porosity or larger fenestrations would allowbone to grow into, or through, the spacers. In addition to enhancing thefixation of the devices, this allows bone and ligament growth andregeneration along the surface of the FLS 120 and/or along the surfaceof the TLS 195, further enhancing the anatomic footprint of thereconstruction. The porosity may be formed into the spacer materialitself, or it may be in the form of holes or penetrations extendingthrough the spacer body, e.g., as exemplified in FIGS. 47-50. Thesefenestrations may extend radially (“side holes”) and/or longitudinally(“end holes”), etc. The fenestrations may be configured such that theside holes and end holes are interconnected, providing a biologiccommunication between the fenestrations.

In other versions of the devices, there may be graft recesses,fenestrations (or a porous material) and small barbed features 250(FIGS. 51-54) on the interference portion of the femoral ligament spacer120 and/or on the interference portion of the tibial ligament spacer 195to resist graft migration. These features may be directed such that theydo not substantially resist the insertion of the ligament spacer intobone, but the barbed feature provides significant resistance to ligamentmovement as a result of the tension imposed on the ligament.

FIGS. 55-57 show fenestrated femoral ligament spacers 120 andfenestrated tibial ligament spacers 195 deployed in bone.

In another version of the invention, the femoral tunnel is drilled in adifferent manner and the femoral ligament spacer 120 is configureddifferently to further expand the anatomic footprint. More particularly,and looking now at FIGS. 58 and 59, the femoral bone tunnel is drilledwith a counterbore at the mouth of the tunnel (i.e., at the entranceinto the joint space). This may be accomplished by first placing theguide pin 25 as before, drilling the smaller tunnel using a cannulateddrill 30A of the first diameter, and then drilling the larger tunnel(i.e., the counterbore) using a cannulated drill 30B of a second, largerdiameter. The guide pin 25, the smaller tunnel, and the larger tunnelare all aligned on the same centerline, i.e., they are co-axial.

Or the tunnels may be drilled in a single drilling step with the use ofa cannulated stepped drill 30C as shown in FIG. 60. The cannulatedstepped drill 30C starts with a smaller diameter, and then steps up to alarger diameter for the counterbore portion of the drilling process.

Drilling the smaller and larger counterbored holes with the steppeddrill bit is shown in FIG. 61.

With this arrangement of bore and counterbore, the FLS 120 is of alarger size and shape than that of the femoral fixation screw 115 (FIG.62). The advantage of this arrangement is to further spread theligaments over a larger elliptical anatomic footprint relative to thesmaller tunnel diameter, thereby allowing the reconstruction to matchwith larger natural anatomic footprints. This may also have theadvantage of using a smaller femoral interference screw 115 and asmaller distal bone tunnel, thereby reducing the size of the distalfemoral tunnel and reducing the amount of bone material removed.

Other details of this configuration of the femoral fixation device 110may also be different from the previously described femoral fixationdevice 110. With the larger FLS 120 and smaller FFS 115, the FLS 120 cannow be assembled from the other end of the FFS 115. FIGS. 63 and 64 showthe exploded view, and the subsequent cross-sectional view, afterassembly of the components to form the complete femoral fixation device110. In this form of the invention, the FFS 115 is assembled through theFLS 120 by passage of the FLS 120 over the FFS threads. The head of theFFS 115 then stops on the inside face of the FLS 120. This arrangementhas the advantage of a simplified manufacturing technique, eliminatingthe need for the reverse threads on the head of the FFS 115 (or othermeans for FLS retention, such as a bonded head to capture the FLS 120 tothe FFS 115). The other features of the femoral ligament spacer 120preferably remain similar to the previously described FLS, such as theligament recesses, the fenestrations and the retaining barbs. Thereverse thread 170 is not utilized in this version of the FLS 120because of the different assembly process and the head features.

The expanded femoral fixation device 110 is then installed (FIGS. 65 and66). The expanded femoral fixation device 110 is slid over the guidewire 25, introduced through the AM portal and brought into proximity ofthe femoral tunnel. The ligaments are then manipulated to theirapproximate anatomic positions and the femoral fixation device 110 istightened into place. As the device is tightened, FFS 115 binds theligament bundles to the femur with an interference fit and FLS 120 bindsthe ligament bundles to the femur with an interference fit. As thedevice is tightened into the femur, the AM and PL bundles 60, 65 arefurther separated by the FLS 120.

In another version of the instrumentation, a specially shaped guide wireaimer 255 (FIG. 67) can be used to show the anticipated footprint of thefemoral and tibial ACL reconstruction. The aimer 255 is constructed as acannulated tube that guides the wire, but with an elliptical face 260 onthe distal end of the tube to align with the femoral surface. The aimer255 can be rotated and moved to closely approximate the femoral ACLinsertion (FIG. 68). The femoral aimer 255 may also have a one or moreprongs (not shown) protruding from its face 260 to register onto thebone surface. The aimer 255 (and the FLS 120 and TLS 195) may bemanufactured with various degrees of angled faces (i.e., at differentangles) that allow the devices to be aligned to individual patientanatomy.

The tunnel is then drilled with the cannulated drill and the slanted,elliptical shape of the femoral tunnel exit approximates the outline ofthe femoral guide wire aimer 255, as shown in FIG. 69.

Similarly, on the tibial side, a pointer 265 with an elliptical shapecan be used to visualize the tibial tunnel as it appears in the jointspace. See FIG. 70.

In another version of the invention, the femoral fixation devicecomprises a simple plug 270 with a canted surface 275. See FIG. 71.

In another version of the invention, the FLS 120 (and TLS 195) may havea different shape than that disclosed above, e.g., the spacers may havea shape such as the exemplary FLS 120 shown in FIG. 72. In this form ofthe invention, there are indentations 280 in the ligament spacer toprovide more space for the graft to reside. The near end of the spacermay be canted or flat (in the preferred form of the FLS 120, theproximal end of the FLS is canted, in the preferred form of the TLS 195,the proximal end of the TLS is flat). Also, instead of mating with athreaded fixation screw, a bullet shaped interference fixation plug 270may form the distal end of the femoral fixation device. The bulletshaped device may have other features such as barbs, ribs, fenestrationsand recesses for providing additional fixation and ligament alignment.

In another version of the femoral ligament spacer 120 (FIG. 73), thehole through the spacer has additional features, such as ahexagonal-shaped bore for engagement with a hex tool (Allen wrench) tohelp rotate the FLS 120 to ensure full perimeter filling of the bonedefect. Rotation of the FLS may also be desirable prior to fullytightening the FLS 120 into place in order to position the AM and PLbundles into their correct anatomic positions. The tool features couldtake on alternate forms such as a slot or spanner wrench, as long as thesize of the central bore in the FLS is adequately maintained to get asmaller wrench through the femoral ligament spacer to engage with thefemoral fixation screw, whereby to tighten the assembly into place. FIG.73 shows the femoral ligament spacer 120 with engagement tool features(hex shape) through the center for rotating the FLS 120 relative to theFFS 115.

Second Preferred Construction and Method of Use

The pages that follow describe alternative, and in some cases preferred,embodiments for the femoral fixation device 110 and the tibial fixationdevice 201 that make up the complete anatomic ACL reconstruction system.The alternative version of the femoral fixation device 110 is describedfirst, followed by the description of the alternative version of thetibial fixation device 201.

The alternative femoral fixation device 110 consists of a femoralfixation screw 115 (FIG. 74) and a femoral ligament spacer 120 (FIG.75).

Looking now at FIG. 74, the femoral fixation screw 115 includes atapered threaded body that presses the graft ligament against the tunneldrilled into the bone so as to make an interference fit. It also has acannulation through its length in order to slide along a guide pin 25 asit is tightened into place. The head of the screw consists of a reversethread 135 for retaining the femoral ligament spacer 120, and a hexsocket 145 in the head for tightening FFS 115 into bone.

Looking now at FIG. 75, the femoral ligament spacer 120 rotates freelyafter assembled onto the femoral fixation screw 115. The femoralligament spacer 120 is made from biocompatible metal, plastic,absorbable ceramic, bone graft material or a combination of thesematerials. The FLS 120 has two or more tab-like features 285 extendingfrom the sides to separate the two or more bundles of the ligamentgraft. Each tab 285 has one (shown) or more teeth (or barbs) 290protruding from the side. The teeth 290 are oriented to provideresistance to being pulled out of the bone tunnel. The front face 155 ofthe FLS 120 is canted, or sloped, to approximately match the surface ofthe bone at the mouth of the bone tunnel, i.e., at approximately theangle 13. A socket 295 is formed into the canted face 155 to permitinsertion of tooling through FLS 120 to tighten the FFS 115, and alsoindentations 300 are formed into canted face 155 for receiving aseparate tool to rotate and align the FLS 120 to its most anatomicposition, or the position where the canted surface is most congruent tothe adjacent bone surface. This device 120 may vary by having additionalbarbs, holes (fenestrations) throughout the device, and/or variousshaped recesses for the graft.

The two components (i.e., the FFS 115 and the FLS 120) are brought intoaxial alignment as shown in FIG. 76. The two components are assembledtogether by use of a reverse (left hand) thread (preferred) or,alternatively, another mechanism such as a right hand thread or aretaining ring or other feature, etc. The left hand thread isadvantageous because there is minimal risk of the FLS 120 coming free ofthe FFS 115 as the device is tightened into place.

FIG. 77 shows the two components 115 and 120 fastened together by use ofthe left hand thread so as to form the complete femoral fixation device110. The threads 135 of the FFS 115 and the threads 170 of the FLS 120are short so that the threads disengage from one another when the FLS120 is fully assembled onto the FFS 115 (FIG. 78), whereupon the threads135 of FFS 115 are rotatably received in enlarged diameter 165 of FLS120. This allows the FLS 120 to spin freely relative to the FFS 115.Thus, the connection between FFS 115 and FLS 120 is similar to theconnection discussed above with respect to the first preferredconstruction of the apparatus.

A cross-sectional view of the assembled femoral fixation device 110(FIG. 78) further illustrates the assembly of the two components 115,120 together. The thread length is short enough so that the threads 135,170 completely disengage when the two pieces are assembled together. Thethreads 135, 170 then form a retaining feature to hold the twocomponents together, while allowing the femoral ligament spacer 120 tospin freely on the femoral fixation screw 115.

In an end view (FIG. 79A) the relationship between the femoral fixationscrew 115 and the femoral ligament spacer 120 is shown. The ligamentgraft is tightly pressed up against the bone tunnel in the area of theFFS 115. The bone tunnel is usually similar to, or just slightly largerthan, the diameter of the FFS 115. The tabs 285 of FLS 120 are at adiameter that is equal to the bone tunnel. The teeth 290 are slightlylarger than the bone tunnel, allowing them to grip into the bone. Theside recesses 180 of FLS 120 are smaller than the bone tunnel andsmaller than the FFS 115 diameter. This allows space for the ligament toreside and be aligned into its desired anatomic position. It alsoprovides an area for the pressure on the ligament to be reduced, thusacting as a stress relief. FIG. 79A shows a femoral ligament spacer 120that is divided into two sections, separated by the tabs 285. In anotherversion of the invention, the spacer could be divided into 3 or moresections to further split and locate the ligament graft, especially forthose cases where a four-stranded ligament graft may be used.

FIG. 79B illustrates the area where the ligament resides between thebone tunnel and the FFS 115 and FLS 120. The cross-hatched arearepresents the ligament graft.

FIGS. 80-82 are additional views which depict the femoral fixationdevice 110 in additional orthogonal views.

FIG. 83 is an oblique view of the femoral fixation device 110, lookingdirectly into the angled surface 155.

Looking now at FIG. 84A, after placement of the guide pin 25 through theAM portal at the angle 13, the femoral fixation device 110 is introducedonto the guide pin 25 to the proximity of the femoral tunnel 40.

FIG. 84B is the same as FIG. 84A, except showing the graft ligament inplace. The portion of the graft ligament entering the tibial tunnel fromthe joint space and located nearest the front (anterior) portion of thetibia (and slightly medial) is the graft replacement for theanteromedial (AM) bundle 60. The portion of the graft entering thetibial tunnel from the joint space and located slightly posterior (andlateral) is the graft replacement for the posterolateral (PL) bundle 65.

A ligament spacer alignment tool 305 is shown in FIG. 85. Two prongs 310protrude from the distal end to engage with the indentations 300 of FLS120, so that ligament spacer alignment tool 305 can be used to turn FLS120 to the appropriate radial position, whereby to align the cantedsurface 155 of FLS 120 with the adjacent bone and whereby toappropriately position graft ligament strands 60, 65 as they emerge fromthe femoral bone tunnel. A through hole 315 is formed through the tool305 for a hex wrench (see below) to pass through. A hub 320 at theproximal end of the tool (shown with scallops) can be turned to rotatethe FLS 120 into desired positions, as will hereinafter be discussed.

In FIG. 86, the ligament spacer alignment tool 305 is shown aligned withthe hex wrench 325. The hex wrench 325 could also be some other profileto mate with the FFS 115, such as a square head, or hexalobular head.

The hex wrench 325 slides through the ligament spacer alignment tool 305as shown in FIG. 87. This allows simultaneous, and independent, rotationand adjustment of the FFS 115 and FLS 120, as will hereinafter bediscussed.

More particularly, in FIG. 88A, the instruments are brought into theproximity of the femoral fixation device 110 by sliding them over theguide pin 25.

The femoral fixation device 110 is approximately between the two strands60, 65 of the ligament graft as shown in FIG. 88B.

The hex wrench 325 (FIGS. 89A and 89B) is advanced closer to the femoralfixation screw 115. Again, from the attachment point into the tibia, theAM bundle 60 is front (anterior) and medial, and the PL bundle 65 isback (posterior) and lateral.

FIG. 90 is an overall view showing the insertion of the femoral fixationdevice 110 (i.e., showing the guide pin 25, the hex wrench 325, the FLSalignment tool 305 and the femoral fixation device 110.

FIGS. 91A and 91B show the hex wrench 325 and the FLS alignment tool 305engaged with the FFS 115 and the FLS 120, respectively. The FLS 120 canbe held steady with FLS alignment tool 305 (by virtue of prongs 310 ofFLS alignment tool 305 being disposed in indentations 300 in FLS 120)while the FFS 115 is rotated by turning the hex wrench 325 (which is anengagement with hex socket 145 of femoral fixation screw 115).

As the FLS 120 gets closer to the femoral tunnel entrance (FIG. 92), itcan be rotated with the FLS alignment tool 305 to appropriately align itwith the bony surface. It is also rotated to position, or urge, theligament graft bundles 60, 65 into their desired anatomic positions.

FIGS. 93A and 93B show the femoral fixation device 110 as it iscompletely seated into the femoral tunnel. The ligament graft iscompletely fixated to the femur, with the ligament graft bundles 60,65located in their proper anatomic positions.

FIGS. 94A and 94B show the final femoral construct with the ligamentbundles 60, 65 placed in their proper anatomic locations. Theinstrumentation is thereafter retracted from the AM portal.

FIGS. 95A and 95B show a larger perspective view of the final construct.The instrumentation is pulled away. The ligament graft bundles are alsoshown traversing the tibial tunnel with sutures extending from bothligament bundles.

In addition to the advantages previously stated, the alternative femoralfixation device described immediately above provides at least thefollowing useful functions in ligament fixation:

(1) Controlled and careful alignment of the tibial ligament spacer 120using the TLS alignment tool 305 to independently to control theorientation of the TLS 120, and thus the alignment of the ligamentgraft, for an improved anatomic reconstruction.

(2) Barbed features 290 on the sides of the TLS 120 enhance the pulloutstrength of the TLS and the overall femoral fixation construct.

(3) More clearly defined ligament recesses in the TLS to provide a moreanatomic reconstruction.

The alternative tibial fixation device 201 (FIGS. 96-101B) is describedbelow. In this version of the invention, the tibial ligament spacer 195is assembled onto the tibial fixation screw 200 in a manner similar tothat of the femoral fixation device 110. However, in the case of thetibial fixation device 201, the TLS 195 is assembled to the leading endof the tibial fixation screw 200 first, and then they are introducedinto the tibial tunnel as a unit.

FIG. 96 is an upper isometric view of the tibial ligament spacer 195.TLS 195 is made from biocompatible metal, plastic, absorbable ceramic,bone graft material or a combination of these materials. The outsideportion of the spacer 195 consists of a body with the two or more tabfeatures 330 protruding from the sides of TLS 195, the angled surface205 at the distal end, one or more bumps 335 formed on the periphery ofthe tabs 330, and a slotted feature 340 for permitting alignment of theTLS 195 within the tibial bone tunnel. The bumps 335 are not the same asthe barbs 250 discussed above, which resist motion primarily in onedirection. The bumps 335 of this construction allow insertion of thedevice through the bone tunnel, but resist passing the device all theway through the bone tunnel as they come into proximity with thecortical layer of bone near the top end of the tibia, near the inside ofthe knee joint.

FIG. 97 is a lower isometric view of the tibial ligament spacer 195.Threads 345 are formed on the inside of the component. The alignmentslot 340 is accessible from the inside of the part. The corners of TLS195 are carefully rounded to permit easy insertion and protection of thesoft tissue ligament graft.

The tibial fixation screw 200 is shown in FIG. 98. The tibial fixationscrew (TFS) 200 may also be made from a variety of materials but, in thepreferred embodiment, comprise a biocompatible metal such as stainlesssteel, cobalt chrome or titanium (the same is true for other fixationscrew components described herein). The distal tip of the TFS 200 has afine pitch thread 350 that engages with thread 345 of the TLS 195. Thefine pitch thread 350 of TFS 200 allows a larger minor thread diameter,permitting a larger cannulation through the body of the TFS 200. Thebody of the tibial fixation screw 200 has larger smooth threads forcompressing the ligament up against the bone tunnel wall. A hole 355passes through the TFS 200, and may be slightly larger than the hole inthe FFS 115. The larger hole (e.g., 3-4 mm diameter) in TFS 200accommodates a special alignment pin (see below) for rotating the TLS195 into the proper orientation while the TLS 195 is disposed in thetibial tunnel.

FIG. 99 is another isometric view of the tibial fixation screw 200. Thehole 355 shown on the distal end of TFS 200 passes all the way throughthe body of the screw. A “relief” area 360 exists between the largerligament-compressing threads formed on the proximal portion of TFS 200(for engaging the ligament) and the fine pitched threads 350 (forengaging the TLS 195). This clearance allows the threads of the TFS 200to disengage from the threads of the TLS 195 (FIG. 101A) so that the TLS195 can rotate freely on TFS 200 after assembly.

FIG. 100 shows the tibial fixation screw 200 and the tibial ligamentspacer 195 aligned for assembly to each other.

The two units (i.e., TLS 195 and TFS 200) are assembled together asshown in FIG. 101A. The threads between the TFS 200 and the TLS 195 maybe left hand or right hand thread. Right handed threads are preferred sothat there is no chance of the TLS 195 disengaging from the TFS 200during the rotational insertion of the TFS 200. After final assembly,there is a clearance between the two components such that the TLS 195can rotate freely on the tip of the TFS 195 without engagement with thefine pitch threads 350 of the TFS 200, thus allowing anatomic adjustmentand placement of the TLS with the tibia. The angle α₂ (hereafterreferred to simply as a in the context describing the TLS) correspondsto the angle of the mouth of the tibial tunnel at the top surface of thetibia. The canted surface 205 of TLS 195 at angle α permits a relativelycongruent and continuous surface to the tibia. FIG. 101B shows a versionwith a conical or wedge-shaped angled surface 356 on the TLS 195 toallow the TLS 195 to be inserted between the ligament grafts more easilyand subsequently engage the threads of the TFS 200 to the ligamentgraft.

The distal end view of the tibial fixation device 201 is shown in FIG.102A. The relationship between the diameters of the device isillustrated. The features that protrude furthest out from the center ofthe device are the retaining bumps 335. The outer surfaces of the tabs330 are approximately the same dimension as the tunnel diameter, thuscreating a definitive separation of the ligaments. The outer diameter ofthe tibial fixation screw 200 is just slightly less (e.g., 0-1 mm less)than the tunnel diameter to tightly compress the ligament against thewalls of the bone tunnel. The recessed portion of the TLS 195 provides aspace for the ligament strands to reside in the final placement. Byappropriately rotating the TLS 195 (see below), the canted face 205 ofTLS 195 is aligned with the tibial plateau and the ligament strands aredirected to their proper anatomic locations. The slot 340 in the TLS 195is used to rotationally position the TLS 195 with the tibial alignmentpin (see below).

FIG. 102B illustrates what the graft strands 60, 65 look like in an endview cross-section. The graft strands 60, 65 are bound on the outside ofthe tibial fixation device 201 by the bone tunnel diameter. The graftstrands 60, 65 are squeezed between the TFS 200 and the bone tunnel, andare directed into position by the tabs 330 and recesses of the TLS 195.The preferred embodiment comprises two tabs 330, but the TLS 195 mightbe further subdivided into three or four sections to furtherdifferentiate the fibers of the ACL reconstruction.

In the associated surgical procedure, the tibial tunnel is drilled withnormal technique, giving consideration to the angles α. The smallerangle α creates a more elliptical tunnel exit at the top of the tibia.

In order to understand the overall system for tibial fixation, severalof the component interfaces are illustrated first.

The tibial fixation device 201 fits over the tibial alignment pin 365(FIG. 103). The slot 340 in the tibial ligament spacer 195 aligns withthe end 370 of the tibial alignment pin 365 (FIG. 105).

The hex wrench 375 (FIG. 104) fits over the tibial alignment pin 365 andcan rotate freely around the pin diameter. Both the hex wrench 375 andthe tibial fixation screw 200 can rotate freely over the tibial guidepin 365.

The end 370 of the tibial alignment pin 365 (FIG. 106) that engages withthe tibial ligament spacer 195 has two flats 380 on opposing sides ofthe pin 365, forming a tab 385 that fits into the slot 340 of the tibialligament spacer 195, whereby to permit tibial alignment pin 365 to turntibial ligament spacer 195 as desired.

The opposite end 390 (FIG. 107) of the tibial alignment pin 365preferably has at least one flat 395 (and may have more) for aligningwith additional instrumentation, e.g., as discussed below.

The overall tibial alignment pin 365 is shown in FIG. 108. The end 370is the tab side that engages with the tibial fixation device 201 (inparticular, with the slot 340 of the TLS 195). The opposite end 390engages with additional instrumentation (see below).

Looking now at FIGS. 109A and 109B, the aforementioned additionalinstrumentation preferably comprises the ligament tensioning bar 400.The ligament tensioning bar 400 includes fasteners 405 (shown asthumbscrews in FIGS. 109A and 109B). The fasteners 405 are used totighten down and secure sutures 70 coming from the ligament graft.Grooves at each end of the bar 400 may be used to wrap the sutures 70prior to tightening with the fasteners 405, e.g., for additionalfixation. The fastener 405 in the middle of the ligament tensioning bar400 tightens down onto the flat 395 on the tibial alignment pin 365,rotationally fixing the tibial tensioning bar 400 to the tibialalignment pin 365. The handle end of the hex wrench 375 is shown inFIGS. 109A and 109B.

The set-up of ligament graft sutures 70 and the ligament tension bar 400is shown in FIG. 109B. The sutures 70 are secured to the ends of theligament graft and wrapped in the grooves on the ligament tensioning bar400. The fasteners 405 are then tightened into place.

FIG. 110 shows the relationship of the tibial fixation device 201, thetibial alignment pin 365, the hex wrench 375 and the ligament tensioningbar 400.

In more detail, FIG. 111A shows the tip of the hex wrench 375 about toengage with the tibial fixation device 201. The ligament graft andsutures are not shown in FIG. 111A for clarity of illustration. The endof the tibial alignment pin 365 is shown engaged with the TLS 195. TheTLS 195 is constrained to rotate only as the tibial alignment pin 365 isrotated, inasmuch as the tibial alignment pin 365 comprises a tab withflats 380 that fits into the slot 340 in the TLS 195. The tibialfixation screw 200 and the hex wrench 375 are free to rotate on thetibial guide pin 365.

FIG. 111B illustrates how the tibial ligament spacer 195 is pushed(using hex wrench 375 to push TFS 200 and hence TLS 195 distally on thetibial alignment pin 365) between the strands 60, 65 of the graftligament (the strands 60, 65 are shown without tension in the strandsfor visualization purposes).

Looking now at FIG. 112, hex wrench 375 can engage with the tibialfixation screw 200. The tibial fixation screw 200 then rotates as thehex wrench 375 is rotated.

The overall system is shown in FIG. 113A (but without the ligament graftor sutures for clarity of illustration).

Looking now at FIG. 113B, the ligament strands 60, 65 and sutures 70 areadded to the drawing, illustrating the overall functional construct. Tosummarize the method, ligament graft sutures 70 are fastened to theligament tensioning bar 400 with the fasteners 405. The tibial alignmentpin 365 is passed through the center hole of the ligament tensioning bar400. The hex wrench 375 and the tibial fixation device 201 are slid overthe tibial alignment pin 365. The tibial alignment pin 365 is thenloosened from the ligament tensioning bar 400 and extended into thetibial tunnel for the length of the tunnel. The tibial alignment pin 365may have markings on its outer surface to indicate the depth that it hastraveled into the tibial tunnel. When the tibial alignment pin 365 hasbeen appropriately inserted into the tibial tunnel, the middle fastener405 on the ligament tensioning bar 400 is tightened so as to secure thetibial alignment pin 365 to the ligament tensioning bar 400. At thispoint, the orientation of the tibial ligament spacer 195, the tibialguide pin 365, and the ligament tensioning bar 400 are rotationallyfixed together, and the orientation of the tibial ligament spacer 195can be rotationally adjusted by rotating the ligament tensioning bar 400about the axis of the tibial guide pin 365. When tension is applied tothe ligament tensioning bar 400, the bar can then be rotated to alignthe tibial ligament spacer 195 into the desired orientation.Specifically, the recesses between the tabs 330 on the tibial ligamentspacer 195 are then adjusted so as to place the ligament strands intotheir anatomic AM and PL locations. The length of the ligamenttensioning bar 400 may be varied as desired so as to space the suturelines to the desired extent and allow more space for the user to gripthe handle of hex wrench 375.

FIG. 114 shows another view of the system, without the ligament graft60, 65 and the sutures 70 being shown.

Next, and looking now at FIG. 115, as tension is applied to the ligamenttensioning bar 400, the hex wrench 375 is turned to advance the tibialfixation device 201 into the tibial tunnel.

FIG. 116 illustrates the final position of the tibial fixation device201 in the tibial tunnel. As discussed above, the ligament graftrecesses are positioned for anatomic location of the AM and PL bundles.

The instrumentation is then disengaged from the tibial fixation device201 as shown in FIG. 117.

The reconstructed ligament construct is then complete. FIG. 118 shows atop view of the ligament construct with the knee in 90 degrees flexion.The top of the tibial fixation device 201 (i.e., the tibial ligamentspacer 195) is shown, as is the tibial fixation screw 200. The recessesbetween the tabs 330 are located so as to properly position the AM andPL bundles. FIG. 118 also shows the femoral fixation device 110.

FIG. 119A is a side view of the tibial and femoral fixation discussedabove. The ligament graft is omitted from this view for clarity ofillustration.

FIG. 119B is a view like that of FIG. 119A, except that it also showsthe graft ligament strands 60, 65. The knee is shown in 90 degrees offlexion. The AM bundle 60 (A-A) crosses the PL bundle 65 (B-B) in thesame way as the natural ACL.

FIG. 119C is another view showing the femoral fixation device 110 andthe tibial fixation device 201. In this view the knee is in fullextension.

FIG. 119D is a side view which illustrates how the AM graft 60 (A-A) isroughly parallel to the PL graft 65 (B-B) when the knee is in fullextension, in the same way as the natural ACL.

FIG. 120A is a front view of the completed construct discussed above.

FIG. 120B is a view like that of FIG. 120A, except showing graftligament strands 60, 65. The AM bundle 60 appears near the front of thetibia at the tibial tunnel. The PL bundle 65 is posterolateral to the AMbundle 60 at the tibial tunnel exit. The construct therefore moreclosely replicates the nominal location and approximate shape of thenatural ACL.

In addition to the advantages listed earlier for the tibial fixationdevice, the present version of the invention includes at least thefollowing advantages and benefits:

(1) An integrated, assembled tibial fixation device, with the tibialfixation screw 200 and the tibial ligament spacer 195 being assembledtogether prior to insertion in the tibia.

(2) An added slot alignment feature in the tibial ligament spacer 195for remote orientation of the TLS 195 into the desired anatomicposition.

(3) Small bumps 335 on both sides of the TLS ligament separation tabs330 allow the assembly into the tibial tunnel, but resist pull throughas the bumps reach the harder tibial cortex at the mouth of the tibialtunnel.

(4) A system of instruments that allows orientation of the TLS,tensioning of the ligaments and tightening of the tibial fixation device201 into its final position, all introduced and fixed into place fromthe outside of the tibia (antegrade), rather than from the inside of thejoint (retrograde).

Alternatives for the Second Preferred Construction and Method of Use

In another embodiment of the invention, and looking now at FIG. 121A,alignment markings 410 are formed on a new device, the spacerorientation guide 415, as well as the ligament spacer alignment tool305, the femoral ligament spacer 120 and the tibial spacer 195. Thealignment markings 410 is placed in a location that is visible andnon-ambiguous in order to create the most flush or even fit with thenative bone surface.

In this form of the invention, after the bone tunnels are drilled intothe femur, the specially shaped spacer orientation guide 415 is insertedinto the femoral tunnel. The spacer orientation guide 415 has a handle420 at one end and a plug 425 at the other end. The plug 425 has twoangled surfaces, one (430) as a guide for the femoral tunnel (the nearsurface) and one (435) as a guide for the tibial tunnel (the farsurface). Alignment marking 410 extends along the plug 425, and thisalignment marking is aligned with the tips, or extreme points, of theelliptical faces 430, 435. The marking location at the extreme points isan example. Other marking locations around the plug 425 may also beused.

Looking now at FIG. 121B, the spacer orientation guide 415 has its plug425 inserted first into the femoral tunnel. The elliptical surface 430of the guide is aligned such that it is approximately even with, orflush with, the femoral tunnel entrance.

The fully inserted spacer orientation guide 415 is shown in FIG. 122.The guide is rotated until the near surface 430 of the plug 425 at theend of the guide is best aligned with the bone surface.

Then the mark 410 on the spacer orientation guide 415 is visualized. Acorresponding mark 440 is made on the adjacent bone surface with asterile, surgical pen or a small awl or pick. See FIG. 123.

In this form of the invention, femoral spacer alignment tool 305includes a corresponding “line” or “marking” 410 corresponding to thetips, or extreme points, or other marked locations, of the ellipse. SeeFIG. 124A. Similarly, the femoral ligament spacer 120 includes analignment marking 410 on its surface as well. See FIG. 124B.

While the guide pin 25 is still in place, the femoral fixation device110 is inserted into the femoral tunnel. The femoral alignment tool 305engages the FLS 120 and rotates the FLS 120 into alignment (i.e., sothat the marking 410 on FLS 120 is aligned with the marking 440 made onthe adjacent bone). Then FLS 120 is tightened into position. See FIG.125.

The aligned FLS 120 is shown in FIG. 126.

In a similar fashion, the tibial fixation device 201 is placed utilizinga mark 445 on the tibial surface. See FIGS. 127-130.

The use of the spacer orientation tool 415, the spacer alignment tool305 and the marked ligament spacers 115, 195 allows an improved fitbetween the ligament graft spacers and the bone surfaces. The resultinglocation of the ligament spacers, both femoral (115) and tibial (195),creates a reconstruction that is closely aligned with the native bonesurfaces. This alignment contributes to anatomic fixation of theligament grafts by giving the surgeon a target to align to whentightening the fixation devices into place.

The benefits of the aligned ligament graft spacers 115, 195 include:

(1) Both the femoral and tibial ligament spacers 115, 195, respectively,are inserted such that they are aligned with the bone surface. Thisallows more natural movement of the ligament, as if bone had alreadyfilled in the space around the ligament graft.

(2) The aligned ligament graft spacers 115, 195 help to ensure ananatomic construction, separating the AM bundle 60 and PL bundle 65 andpositioning them into their correct anatomic positions.

(3) The aligned ligament graft spacers 115, 195 provide a clear targetfor aligning the ligament spacers.

Modifications Of The Preferred Embodiments

It should be understood that many additional changes in the details,materials, steps and arrangements of parts, which have been hereindescribed and illustrated in order to explain the nature of the presentinvention, may be made by those skilled in the art while still remainingwithin the principles and scope of the invention.

1. Apparatus for reconstructing a ligament, the apparatus comprising: afixation device for maintaining a graft ligament in a bone hole, thefixation device comprising: a fixation screw comprising a body havingscrew threads formed thereon; and a ligament spacer mounted to thefixation screw, the ligament spacer comprising a canted face disposedopposite the fixation screw; such that when a graft ligament is disposedwithin a bone hole, the fixation screw and ligament spacer may beadvanced into the bone hole alongside the graft ligament so that thefixation screw creates an interference fit between the graft ligamentand the wall of the bone hole, and the ligament spacer creates aninterference fit between the graft ligament and the wall of the bonehole, with the canted face of the ligament spacer being aligned with theadjacent surface of the bone.
 2. Apparatus according to claim 1 whereinthe ligament reconstruction comprises an ACL reconstruction, the bonehole extends into the femur, and the ligament fixation device comprisesa femoral fixation device, and further wherein the fixation screwprecedes the ligament spacer into the bone hole.
 3. Apparatus accordingto claim 2 wherein the ligament spacer is attached to the fixation screwwhen the fixation screw and ligament spacer are advanced into the bonehole alongside the graft ligament.
 4. Apparatus according to claim 3wherein the ligament spacer is rotatably mounted to the fixation screw.5. Apparatus according to claim 4 wherein the fixation screw comprises adistal end and a proximal end, a neck extending proximally from theproximal end of the fixation screw, and a threaded head extendingproximally from the neck, and further wherein the ligament spacercomprises a distal end and a proximal end, a bore extending from thedistal end to the proximal end, a bore enlargement disposed intermediatethe bore, and internal screw threads disposed on the bore distal to thebore enlargement, the threaded head of the fixation screw being sized tomake threaded engagement with the internal screw threads of the ligamentspacer, and the bore enlargement in the ligament spacer being sized torotatably accommodate the threaded head of the fixation screw, such thatthe distal end of the ligament spacer can be screwed over the threadedhead of the fixation screw, whereby to rotatably mount the ligamentspacer to the proximal end of the fixation screw.
 6. Apparatus accordingto claim 5 wherein the threaded head of the fixation screw comprises adrive element for turning the fixation screw, and further wherein thedrive element of the fixation screw may be accessed through the bore ofthe ligament spacer when the ligament spacer is rotatably mounted to thefixation screw.
 7. Apparatus according to claim 6 wherein the driveelement comprises a hex recess.
 8. Apparatus according to claim 1wherein the graft element comprises a plurality of graft strands, andfurther wherein the ligament spacer comprises a peripheral geometryconfigured to separate the plurality of graft strands within the bonehole.
 9. Apparatus according to claim 8 wherein the ligament spacercomprises at least one pair of diametrically opposed tabs, and furtherwherein each of the plurality of graft strands is disposed between twoof the tabs.
 10. Apparatus according to claim 1 wherein the ligamentspacer comprises a rotation element for turning the ligament spacerwhile the ligament spacer is attached to the fixation screw. 11.Apparatus according to claim 10 wherein the rotation element comprises apair of diametrically opposed indentations formed in the ligamentspacer.
 12. Apparatus according to claim 1 wherein the ligamentreconstruction comprises an ACL reconstruction, the bone hole extendsthrough the tibia, and the ligament fixation device comprises a tibialfixation device, and further wherein the ligament spacer precedes thefixation screw into the bone hole.
 13. Apparatus according to claim 12wherein the fixation screw is attached to the ligament spacer after theligament spacer and fixation screw are advanced into the bone holealongside the graft ligament.
 14. Apparatus according to claim 13wherein the ligament spacer is advanced into the bone hole from theinterior of the joint and the fixation screw is advanced into the bonehole from the front of the tibia.
 15. Apparatus according to claim 13wherein the ligament spacer comprises a distal end and a proximal end, aneck extending proximally from the proximal end of the ligament spacer,and a threaded head extending proximally from the neck, with the cantedface being disposed on the distal end of the ligament spacer, andfurther wherein the fixation screw comprises a distal end and a proximalend, a bore extending from the distal end to the proximal end, and acounterbore opening on the distal end of the fixation screw andextending proximally, the threaded head on the ligament spacer and thecounterbore of the fixation screw being sized to threadingly engage oneanother, such that the distal end of the fixation screw can be screwedover the threaded head of the ligament spacer, whereby to mount theligament spacer to the distal end of the fixation screw.
 16. Apparatusaccording to claim 15 wherein the bore of the fixation screw comprises adrive element for turning the fixation screw.
 17. Apparatus according toclaim 16 wherein the drive element comprises a hex recess.
 18. Apparatusaccording to claim 12 wherein the graft element comprises a plurality ofgraft strands, and further wherein the ligament spacer comprises aperipheral geometry configured to separate the plurality of graftstrands.
 19. Apparatus according to claim 18 wherein the ligament spacercomprises at least one pair of diametrically opposed tabs, and furtherwherein each of the plurality of graft strands is disposed between twoof the tabs.
 20. Apparatus according to claim 12 wherein the ligamentspacer comprises a rotation element for turning the ligament spacerwhile the ligament spacer is disposed in the bone hole.
 21. Apparatusaccording to claim 20 wherein the rotation element comprises anon-circular opening formed in the ligament spacer.
 22. Apparatus forreconstructing a ligament, the apparatus comprising: a first fixationdevice for maintaining a graft ligament in a first bone hole, the firstfixation device comprising: a first fixation screw comprising a bodyhaving screw threads formed thereon; and a first ligament spacer mountedto the first fixation screw, the first ligament spacer comprising afirst canted face disposed opposite the first fixation screw; such thatwhen a graft ligament is disposed within the first bone hole, the firstfixation screw and first ligament spacer may be advanced into the firstbone hole alongside the graft ligament so that the first fixation screwcreates an interference fit between the graft ligament and the wall ofthe first bone hole, and the first ligament spacer creates aninterference fit between the graft ligament and the wall of the firstbone hole, with the first canted face of the first ligament spacer beingaligned with the adjacent surface of the first bone; and a secondfixation device for maintaining the graft ligament in a second bonehole, the second fixation device comprising: a second fixation screwcomprising a body having screw threads formed thereon; and a secondligament spacer mounted to the second fixation screw, the secondligament spacer comprising a second canted face disposed opposite thesecond fixation screw; such that when the graft ligament is disposedwithin the second bone hole, the second fixation screw and secondligament spacer may be advanced into the second bone hole alongside thegraft ligament so that the second fixation screw creates an interferencefit between the graft ligament and the wall of the second bone hole, andthe second ligament spacer creates an interference fit between the graftligament and the wall of the second bone hole, with the second cantedface of the second ligament spacer being aligned with the adjacentsurface of the second bone.
 23. Apparatus according to claim 22 whereinthe ligament reconstruction comprises an ACL reconstruction, the firstbone hole extends into the femur, and the first ligament fixation devicecomprises a femoral fixation device, and further wherein the firstfixation screw precedes the first ligament spacer into the first bonehole, and further wherein the second bone hole extends through thetibia, and the second ligament fixation device comprises a tibialfixation device, and further wherein the second ligament spacer precedesthe second fixation screw into the second bone hole.
 24. (canceled)